Is Blender future proof?
Other than a very big change from 2.49 to 2.5, the interface and main functions of Blender have stayed the same for a long time.

The logic and workflow in which Blender operates seems to be very stable, and works perfectly across Operating Systems. It's worth noting tha it runs smoothly on a very wide variety of hardware. Modest or old computers will work just fine but it will make good use of the resources of a powerful computer.

As most programs, blender keeps improving with some eventual breakups and minor changes; but backwards compatibility in blender is superior to most software out there. It does not abandon its users to their own devices or makes the files incompatible to in order force users to use the newest version. Blender, being free/libre and open source, does not have to respond to a particular market share or stock holders... There is no planned obsolescence for monetary gain.

Big changes are made mostly to accommodate newer technologies or to make the program more versatile (and sometimes easier to use).

Blender does not force its users to monthly payments, nor does it have a "light" (crippled) version, an "intermediate", "pro" or creative suites for VIPs.  The same program can be used for a wide variety of purposes, from films and games, to 3D printing or Architectural rendering, or math or science visualizations. 

So many people are using blender for all kinds of uses now, that commercial rendering engines are making ports to render blender projects. I can only see that kind of support growing, as blender is indeed getting wider recognition as a serious 3D tool. There are also some companies creating modified versions of blender for web content  creation, biology scientific modelling and easy game asset creation. There is a growing a number of render farm services and cloud computing companies that support Blender as well.

Something worth mentioning is that the Blender Foundation has kept every version of the software (dating to v1.0) available for download. So even if your file were to be outdated, you can always go to blender.org, download the version used to create the file and retrieve your information.

The path for Blender's future seems quite bright and the developers are very open about their intentions and their road map.

But foreseeing the future is beyond the scope of this site.

Will blender's technology outlast that of the blender in your kitchen? Probably not.

In the meantime if someone out there finds an add-on or a modifier to render the future in real-time please post it here.